The bipolar battery is a battery that forms a positive electrode layer on one surface of a collector and a negative electrode layer on another surface. These surfaces are arranged in an alternating fashion with an electrolyte layer that performs ion replacement between each bipolar electrode. If the companions between the electrodes at the ends of this kind of bipolar battery come in contact, there is a short circuit, and in addition, if the electrolyte layers come into contact, a liquid junction would be formed.
To counteract these problems, some bipolar batteries utilize a coating of an insulating material on the periphery of a unit battery formed by sandwiching the separator that has been immersed in an electrolyte between the positive and negative electrodes. In addition, the periphery of the unit battery is formed by laminating using a conducting foil to prevent a liquid junction or short circuit between each electrode.